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<html lang="en">
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    <meta charset="UTF-8" />
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    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      let index = -1;
      let search = function (arr, item) {
        for (let i = 0; i < arr.length; i++) {
          if (arr[i] === item) {
            index = i;
            break;
          }
        }
        return index;
      };
      let name = ["jack", "lisa", "jennie", "rose", "pink"];
      let res = search(name, "jennie");
      res === -1 ? console.log("没有找到") : console.log("下标为:" + res);
    </script>
  </body>
</html>
